1. Field of the Invention
The present invention relates to a method for manufacturing an aluminum plate, an aluminum plate, a collector for a storage device, and a storage device.
2. Description of the Related Art
In recent years, in response to the development of portable devices such as personal computers and mobile phones, hybrid vehicles, electric vehicles, and the like, the demand for storage devices (particularly, lithium ion capacitors, lithium ion secondary batteries, and electric double layer capacitors) as power supplies has increased.
It is known that, as electrode collectors that are used for positive electrodes or negative electrodes in the above-described storage devices (hereinafter, simply referred to as “the collectors”), aluminum plates are used.
For example, JP2013-077734A describes the use of metal foils having a plurality of through holes as collectors and also describes aluminum, copper, and the like as materials therefor ([Claim 1] and [0021]).
In addition, JP2012-151395A describes the use of film-like collectors having through holes as collectors and also describes the use of aluminum, stainless steel, and the like as positive electrode collectors ([Claim 1] and [0053]).
In addition, JP2010-186779A describes metal foils having a number of through holes formed in places to which active materials are attached as positive and negative electrodes and also describes aluminum foils as positive electrode collectors ([Claim 1] and [0016]).
Similarly, WO2008/078777A describes the use of “collectors made of aluminum etched foils which have a thickness in a range of 20 μm to 45 μm, an apparent density in a range of 2.00 g/cm3 to 2.54 g/cm3, and a number of through holes that penetrate front and rear surfaces having an air permeability in a range of 20 s to 120 s” as coated electrodes ([Claim 1]) and also describes that 80% or more of the through holes in the collectors have hole diameters in a range of 1 μm to 30 μm ([Claim 2]).
In addition, WO2011/004777A describes “an aluminum penetrated foil comprising Fe: 5 weight ppm to 80 weight ppm, Si: 5 weight ppm to 100 weight ppm, and Cu: 10 weight ppm to 100 weight ppm with a remainder being Al and inevitable impurities, wherein (1) a foil thickness is 50 μm or less, (2) a plurality of through holes reaching a rear surface from a foil front surface are provided, and (3) a ratio [c/t] of a vertical through hole occupancy c (%) in the aluminum penetrated foil to the foil thickness t (μm) is 1.4 or greater.” ([Claim 1]) and also describes that the inner diameters of the through holes are in a range of 0.2 μm to 5 μm ([Claim 3]).